package edu.wust;

import java.math.BigInteger;

public class exam25 {
    public static int fatorsum(int num){
        int sum=0,half=num>>1;
        for(int i=1;i<=half;i++){
            if(num%i==0)
                sum+=i;
        }
        return sum;
    }
    public static void main(String[] args) {
        int count=2;
        BigInteger a=new BigInteger("1"),b=new BigInteger("1"),c=new BigInteger("2"),temp,end=new BigInteger("1");
        for(int i=0;i<999;i++)
            end=end.multiply(new BigInteger("10"));
        while(c.compareTo(end)!=1){
            temp=b;
            c=a.add(b);
            b=c;
            a=temp;
            count++;
        }
        System.out.println(count);
    }
}

